The cubs' public debut marked a happy triumph for zoo staffers, who in October balanced joy for their birth with mourning for their mother, lioness Badu, who died from complications days after giving birth.

"It is so great to see that we've got these two cubs and their adopted sister, the three of them out there," Ballentine said. "They really bring a lot of joy to the animal staff."

After Luke and Leia were born, Badu, just 31/2 years old, showed distress and signs she was attempting to deliver a third cub. Zoo officials performed a cesarean section, and two more cubs were delivered but neither survived. Badu died several days later.

Zoo staff have been caring for the lion cubs in Badu's absence. Luke weighs about 45 pounds, Leia and Zuri each about 40 pounds. They have yet to be introduced to the zoo's adult lions, Cuma and Hassan. Cold weather has also restricted the public's access to them.

On Saturday, with temperatures reaching into low 60s, zookeepers led the cubs out of their den and into a public-viewing area for the first time, Ballentine said. At the time, there were some 200 people in the area.

Leia "kind of goes full charge," is the "feisty and independent" one — just like her mother was — and immediately started exploring, Ballentine said.

Luke "kind of hangs back," preferring to see what his sister does first, but also having fun pouncing on her and Zuri, Ballentine said.

Zuri is the "cautious cat," Ballentine said. She spent a good amount of time watching all the people watching her.

People took turns holding young children up to the glass. "Folks were really, really great," Ballentine said.

The cubs were out from 10:30 a.m. until 11:15 a.m., after which they were "very tired," she said.

By 3 p.m., more than 3,000 people had entered the zoo, Ballentine said — more visitors than the zoo had in all of January. Many were zoo members who have been following the cubs' story, she said.

The cubs will be on display again Sunday, from 10:30 a.m. to 11:15 a.m.

With more cold weather forecast for next week, Ballentine said there is still no set schedule for when the lion cubs will be on display again in the future.

However, as soon as "the weather breaks," Ballentine said, zoo staff will train the cubs to "go in and out of the yard themselves."